From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 12144C433C1 for ; Sun, 28 Mar 2021 07:51:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CF5A261924 for ; Sun, 28 Mar 2021 07:51:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231182AbhC1Huo (ORCPT ); Sun, 28 Mar 2021 03:50:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44826 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229724AbhC1HuT (ORCPT ); Sun, 28 Mar 2021 03:50:19 -0400 Received: from ustc.edu.cn (email6.ustc.edu.cn [IPv6:2001:da8:d800::8]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id C0FD8C061762; Sun, 28 Mar 2021 00:50:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mail.ustc.edu.cn; s=dkim; h=Received:From:To:Cc:Subject:Date: Message-Id:MIME-Version:Content-Transfer-Encoding; bh=opXlKr1Le0 DyEohzhyA9nRDoPFWP03/6sChBMUspOCQ=; b=Cnktk34WDWZx02DAJFasm1L6o9 kq0SgmYsQ6TeMVIknJTB3E/1adOwCGpgEffVPEFf3okR8kqkMC7KmZHS6WIESNEL KDX5iDpaU5UL4xCZhdTxc59ei05VLrUUx/UieWnElpcpnP+WyoKpDZw8FsZGdYez 03W5DGvF7dAotsShY= Received: from ubuntu.localdomain (unknown [202.38.69.14]) by newmailweb.ustc.edu.cn (Coremail) with SMTP id LkAmygBHT0syNWBgtaxcAA--.3415S4; Sun, 28 Mar 2021 15:50:10 +0800 (CST) From: Lv Yunlong To: khc@pm.waw.pl, davem@davemloft.net, kuba@kernel.org Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Lv Yunlong Subject: [PATCH] drivers/net/wan/hdlc_fr: Fix a double free in pvc_xmit Date: Sun, 28 Mar 2021 00:50:08 -0700 Message-Id: <20210328075008.4770-1-lyl2019@mail.ustc.edu.cn> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID: LkAmygBHT0syNWBgtaxcAA--.3415S4 X-Coremail-Antispam: 1UD129KBjvdXoW7JrW5Ar4kWr1kAr13uw4kWFg_yoWkKFbEkr ZYv3WxC3y8Kw1qqr4kWF13Aryaka1kXFWkZFWfKr9xJ347ur97CwsavF97GryUG3ySkFW7 JrWkZFykCrWrWjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUIcSsGvfJTRUUUbsAFF20E14v26r4j6ryUM7CY07I20VC2zVCF04k26cxKx2IYs7xG 6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8w A2z4x0Y4vE2Ix0cI8IcVAFwI0_Xr0_Ar1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr0_ Cr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_GcCE3s 1lnxkEFVAIw20F6cxK64vIFxWle2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IE w4CE5I8CrVC2j2WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMc vjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v 4I1lc2xSY4AK67AK6r4xMxAIw28IcxkI7VAKI48JMxC20s026xCaFVCjc4AY6r1j6r4UMI 8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAFwI0_JrI_JrWlx4CE17CEb7AF67AK xVWUAVWUtwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20xvE14v26r1j6r1xMIIF0xvE2Ix0cI 8IcVCY1x0267AKxVWUJVW8JwCI42IY6xAIw20EY4v20xvaj40_Wr1j6rW3Jr1lIxAIcVC2 z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxVW8JVW8JrUvcSsGvfC2KfnxnU UI43ZEXa7VUbVHq5UUUUU== X-CM-SenderInfo: ho1ojiyrz6zt1loo32lwfovvfxof0/ Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org In pvc_xmit, if __skb_pad(skb, pad, false) failed, it will free the skb in the first time and goto drop. But the same skb is freed by kfree_skb(skb) in the second time in drop. Maintaining the original function unchanged, my patch adds a new label out to avoid the double free if __skb_pad() failed. Fixes: f5083d0cee08a ("drivers/net/wan/hdlc_fr: Improvements to the code of pvc_xmit") Signed-off-by: Lv Yunlong --- drivers/net/wan/hdlc_fr.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/wan/hdlc_fr.c b/drivers/net/wan/hdlc_fr.c index 0720f5f92caa..4d9dc7d15908 100644 --- a/drivers/net/wan/hdlc_fr.c +++ b/drivers/net/wan/hdlc_fr.c @@ -415,7 +415,7 @@ static netdev_tx_t pvc_xmit(struct sk_buff *skb, struct net_device *dev) if (pad > 0) { /* Pad the frame with zeros */ if (__skb_pad(skb, pad, false)) - goto drop; + goto out; skb_put(skb, pad); } } @@ -448,8 +448,9 @@ static netdev_tx_t pvc_xmit(struct sk_buff *skb, struct net_device *dev) return NETDEV_TX_OK; drop: - dev->stats.tx_dropped++; kfree_skb(skb); +out: + dev->stats.tx_dropped++; return NETDEV_TX_OK; } -- 2.25.1